Biological air pollution control has been used on an increasing basis in recent years to cleanse noxious and odorous gases, such as those emanating from sewage treatment plants. In addition to sewage treatment plants, biofilters are useful for treating the effluent gases from many other processes, such as farming, rendering plants, coffee roasters, foundries, and composting plan.
Biological filtration systems, or biofiltration utilize a bed of stacked biofilter material such as compost, tree bark, peat, heather or soil, generally three or more feet deep above the BioFloor. The containment gas from the sewage treatment plant or other sources is blown upward though the biofilter material via the plenum created by the Biofloor system. The material in the biofiltration bed provides an environment for a diverse culture of microorganisms, which degrade the gaseous pollutants as they pass through the biofilter.